This move has been the favorite of strong GMs recently.
1... e7e5  2. b1c3  2... f8b4 The third most popular move, but not worse than 2...Nf6 or 2...Nc6. 3. c3d5 The natural reply, forcing Black to defend the bishop. 3... b4e7 3...Bc5 and 3...a5 are also popular options.